Basic

The escalating political tensions in the US in the wake of fresh revelations around Donald Trump could affect Africa in two ways, notes John Stremlau. Firstly, the timing of an impeachment inquiry threatens to divert attention from international efforts to deal with climate change - a development the continent can ill afford. And if Trump is found to have abused his power and yet retains it, he could also set a poor example for a continent that still suffers from democratic setbacks.

At up to 170 tonnes, the blue whale is the largest animal in the world – in fact, scientists reckon it’s probably the largest animal ever, even including dinosaurs. We know this because scientists have painstakingly chopped up and weighed individual chunks of whale carcass. It’s not particularly easy or accurate, and it relies on finding a dead whale or killing one. Scientists have long wanted a better way to assess the weight of a living whale in its natural habitat. And now they may have found one. Fredrik Christiansen reports on how to weigh a whale (without killing it first).